| 2006 №01 (04) | 2006 №01 (06) |
The Paton Welding Journal, 2006, #1, 30-33 pages
Increasing fatigue resistance of welded joints by high-frequency mechanical peening
V.V. Knysh, A.Z. Kuzmenko, O.V. Vojtenko
E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
Given are the results of fatigue tests of welded joints treated by strengthening high-frequency mechanical peening right after welding, as well as after operating for 50 % (and more) of their fatigue life. Factors were determined, which promote increase in welded joint fatigue resistance after application of this treatment, namely lowering of stress concentration coefficient, inducing of compressive residual stresses and strain hardening of metal surface layer.
Keywords: welded joint, mechanical peening, fatigue limit, cyclic fatigue life, fatigue curve, residual stresses, stress concentration coefficient, strain hardening, peening efficiency
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